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/*
* This file is part of the coreboot project.
*
* Copyright 2013 Google Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdint.h>
#include <delay.h>
#include <timer.h>
#include "clk.h"
static struct monotonic_counter {
int initialized;
struct mono_time time;
uint64_t last_value;
} mono_counter;
static const uint32_t clocks_per_usec = MCT_HZ/1000000;
void timer_monotonic_get(struct mono_time *mt)
{
uint64_t current_tick;
uint64_t usecs_elapsed;
if (!mono_counter.initialized) {
mct_start();
mono_counter.last_value = mct_raw_value();
mono_counter.initialized = 1;
}
current_tick = mct_raw_value();
usecs_elapsed = (current_tick - mono_counter.last_value) /
clocks_per_usec;
/* Update current time and tick values only if a full tick occurred. */
if (usecs_elapsed) {
mono_time_add_usecs(&mono_counter.time, usecs_elapsed);
mono_counter.last_value = current_tick;
}
/* Save result. */
*mt = mono_counter.time;
}
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